import { strUnicode2Ansi, strAnsi2Unicode} from './StringUtils.js'
export function stringEncodeBase64(string) {
  return encode64(string).toUpperCase();
}

var keyStr = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=";
function encode64(input) {
  input = strUnicode2Ansi(input);
  var output = "";
  var chr1,
    chr2,
    chr3 = "";
  var enc1,
    enc2,
    enc3,
    enc4 = "";
  var i = 0;
  do {
    chr1 = input.charCodeAt(i++);
    chr2 = input.charCodeAt(i++);
    chr3 = input.charCodeAt(i++);
    enc1 = chr1 >> 2;
    enc2 = ((chr1 & 3) << 4) | (chr2 >> 4);
    enc3 = ((chr2 & 15) << 2) | (chr3 >> 6);
    enc4 = chr3 & 63;
    if (isNaN(chr2)) {
      enc3 = enc4 = 64;
    } else if (isNaN(chr3)) {
      enc4 = 64;
    }
    output = output + keyStr.charAt(enc1) + keyStr.charAt(enc2) + keyStr.charAt(enc3) + keyStr.charAt(enc4);
    chr1 = chr2 = chr3 = "";
    enc1 = enc2 = enc3 = enc4 = "";
  } while (i < input.length);
  return output;
}

function decode64(input) {
  var output = "";
  var chr1,
    chr2,
    chr3 = "";
  var enc1,
    enc2,
    enc3,
    enc4 = "";
  var i = 0;
  if (input.length % 4 != 0) {
    return "";
  }
  var base64test = /[^A-Za-z0-9\+\/\=]/g;
  if (base64test.exec(input)) {
    return "";
  }
  do {
    enc1 = keyStr.indexOf(input.charAt(i++));
    enc2 = keyStr.indexOf(input.charAt(i++));
    enc3 = keyStr.indexOf(input.charAt(i++));
    enc4 = keyStr.indexOf(input.charAt(i++));
    chr1 = (enc1 << 2) | (enc2 >> 4);
    chr2 = ((enc2 & 15) << 4) | (enc3 >> 2);
    chr3 = ((enc3 & 3) << 6) | enc4;
    output = output + String.fromCharCode(chr1);
    if (enc3 != 64) {
      output += String.fromCharCode(chr2);
    }
    if (enc4 != 64) {
      output += String.fromCharCode(chr3);
    }
    chr1 = chr2 = chr3 = "";
    enc1 = enc2 = enc3 = enc4 = "";
  } while (i < input.length);
  return strAnsi2Unicode(output);
}
